Chemical Diversity and α-Glucosidase Inhibitory Activity in Needles Essential Oils of Four Pinus Species from Northwestern Himalaya, India.

This work describes the study of the chemical profiling and α-glucosidase inhibitory activity of essential oils (EOs) from four Pinus species (P. wallichiana, P. patula, P. roxburghii and P. gerardiana). The identification and quantification of EOs metabolites were performed by GC/MS, GC-FID and 13 C-NMR. The needles of P. wallichiana and P. gerardiana presented the highest oil yields (0.35 % and 0.36 %, respectively). Twenty-four constituents were characterized in among samples exhibiting 93.8-97.7 % of the total EOs. The components and yields of the targeted samples were varied according to the species. Major components of the oils were α-pinene (20.5-34.1 %), β-pinene (1.4-53.0 %), δ-3-carene (0.2-47.0 %), limonene (1.7-13.4 %), β-phellandrene (0.2-23.4 %), β-myrcene (1.8-7.2 %) and α-terpinolene (0.6-7.9 %). The extracted EOs showed strong α-glucosidase inhibitory activity, which was close to the positive control, acarbose. This study showed that the EOs of Pinus species may be used as natural antidiabetic.